It must be hard to be a celebrity. What with all the attention and fortune and whatnot. But it must be even harder to be a celebrity with a celebrity doppelganger.

For years I have struggled with distinguishing a few sets of stars. Let’s start with the first.

Keira Knightly & Natalie Portman 

Yes, I know they are not the same people BUT they do look shockingly alike. Can you imagine auditioning for a role and knowing you were up against each other? It is one thing if you’re Natalie Portman and you lose a role to January Jones. Clearly they were not looking for what you had to offer. But if Keira snakes a role out from under you? Well I would have to think you’d be pretty ticked.

Next up and the duo that really gets my head spinning: Christopher Walken & Jon Voigt

I’m not entirely convinced that these two aren’t the same people. Have you ever seen them together? Have you ever seen Walken look really mad? Or Voigt extremely hilarious? No. I stand by my theory that they are just alter egos of each other.

And now, for some more obscure but equally convincing doubles…

Salim (Madhur Mittal from Slumdog Millionaire) & Bruno Mars

I’ve been ruminating over this one for a while. Slumdog Millionaire came out before Bruno Mars was a big success. When I first saw Bruno popping up places, my initial reaction was “hey, the mean and then self-sacrificing brother from Slumdog Millionaire is a singer now.” Turns out that he’s not. But that doesn’t make them look any less similar.

Jason Trawick (aka Britney’s man) & Sam Tramell

God these 2 are alike. Shaggy hair? Check. Manicured stubble? Check. Affinity for plaid shirts? You know it. These scruff muffins also clean up really nicely too. It must be a relief for Britney to know that if she continues to go through men like she goes through money, that at least she has a pretty bang-on stand in. (PS – I love you Britney).

So what do you think? Any celeb doubles that really throw you for a loop?